2021-12-22 03:27:28

by Jason Wang

Subject: [PATCH] ipmi: ssif: replace strlcpy with strscpy

The strlcpy should not be used because it doesn't limit the source
length. So that it will lead some potential bugs.

But the strscpy doesn't require reading memory from the src string
beyond the specified "count" bytes, and since the return value is
easier to error-check than strlcpy()'s. In addition, the implementation
is robust to the string changing out from underneath it, unlike the
current strlcpy() implementation.

Thus, replace strlcpy with strscpy.

Signed-off-by: Jason Wang <[email protected]>
---
drivers/char/ipmi/ipmi_ssif.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index 48aab77abebf..ba779f1abb5b 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -1354,7 +1354,7 @@ static int ssif_detect(struct i2c_client *client, struct i2c_board_info *info)
if (rv)
rv = -ENODEV;
else
- strlcpy(info->type, DEVICE_NAME, I2C_NAME_SIZE);
+ strscpy(info->type, DEVICE_NAME, I2C_NAME_SIZE);
kfree(resp);
return rv;
}
--
2.34.1

2021-12-22 14:01:19

by Corey Minyard

Subject: Re: [PATCH] ipmi: ssif: replace strlcpy with strscpy

On Wed, Dec 22, 2021 at 11:27:07AM +0800, Jason Wang wrote:
> The strlcpy should not be used because it doesn't limit the source
> length. So that it will lead some potential bugs.
>
> But the strscpy doesn't require reading memory from the src string
> beyond the specified "count" bytes, and since the return value is
> easier to error-check than strlcpy()'s. In addition, the implementation
> is robust to the string changing out from underneath it, unlike the
> current strlcpy() implementation.
>
> Thus, replace strlcpy with strscpy.

Ok, thanks for the patch.

-corey

>
> Signed-off-by: Jason Wang <[email protected]>
> ---
> drivers/char/ipmi/ipmi_ssif.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
> index 48aab77abebf..ba779f1abb5b 100644
> --- a/drivers/char/ipmi/ipmi_ssif.c
> +++ b/drivers/char/ipmi/ipmi_ssif.c
> @@ -1354,7 +1354,7 @@ static int ssif_detect(struct i2c_client *client, struct i2c_board_info *info)
> if (rv)
> rv = -ENODEV;
> else
> - strlcpy(info->type, DEVICE_NAME, I2C_NAME_SIZE);
> + strscpy(info->type, DEVICE_NAME, I2C_NAME_SIZE);
> kfree(resp);
> return rv;
> }
> --
> 2.34.1
>